Air regulator



Feb. 2o, 1945. F R FORSS l 2,369,779

AIR REGULATOR Filed May 15', 1943 Patented Feb. 20, 19.45

- UNITED. .sm'rigj s, PATENT lor-FICE 3 Claims.

This invention relates to improvements in air.

regulators for portable pneumatic tools and more particularly for relatively light, fast hittingchipping and riveting hammers.

The general purpose and object of my invention is yto provide an air regulator of`a construction which'is normally sealed against air leakage at all times Ito-prevent the objectionable hissing lof, the air through the regulator when the tool is under pressure Aand lying idlel as in the previous constructions.`

the fair. regulator shaft which adjusts it with a valve member which by spring means is normally Seated to prevent' air leakage along lthe shaft in f' lanyposition of adjustment of the regulator.

A further object yof my invention is to provide the valve `memberand litsseat of a tapered, circular kctmstruction whereby 'a leak proof connection is lmaintainedbetween the valve and 'its seat in the lapping action which occurs vin turning the valve member by the shaft in adjusting the regulator.

Aifurther object o'fmy invention is to employ the spring means which normally seats vthe valve .as a part of the'v check-construction which holds the shaft element against accidental 'turning to .maintain the adiustmentvof the regulator. 1 The'inventlon `consists l'further in the features of construction hereinafter describedand claimed.

Fig. 4 is a sectional view taken on line 4 4 of F.ig.,2; and

Fig. 5 is aside view ofthe regulator plunger to be flater described.

In the' accompanying drawing, lindicates the barrel of a portable, relatively light, fast hitting lchipping or riveting hammer and in which barrel lreclprocates aliammering piston to generate the power blows produced by these tools. Screwed'on f A further object oi my invention is to provide the upper or inner -end ofthe barrel is ahandle barrel in substantially right angular relation thereto and mounting a throttle valve for controlling the ow of compressed air to the barrel for reciprocating the hammering piston therein asin tools of this character. The handle member '2 where it is connected with the upper end Aof the barrel encloses Va distributing valve structure f3 which automatically controls the admission-of compressed air tothe opposite ends of the barrel or the cylinder which the barrel provides for the hammer piston. The handle 2 provides an air supply chamber 4 for the distributing valve 3 and said chamber f4 isfsupplied with compressed air vfrom Athe handle member 2 through a mainv supply passage -therein'next to be described.

The main supply passage in thehandle kmember 2 extends-longitudinally therethrough and is comprised of two interconnected off-set sections, an outer section 5 to whichthe inlet nipple 6 for the lair hose (not shown) is connected at the outer end ofthe handle, andan inner section I which leads to the supply chamber 4 at the distributing valve 3. The passage 'sections 5, 1 are interconnected intermediate the ends'of the handle member 2 by a cross-port 8 at their adjacent ends as shown in Fig. 1.' n

Located within `the outer section 5 of the main supply passage lis a throttle valve assembly com- '.prising a bushing 9 having a valve seat ID at a port I I for a normally seated, spring biased valve mem- 'ber I 2 as shown in Fig. l. `The bushing 9 has two sets of ports I3, I4'on opposite sides of the valve memberl I2, the ports I3 vconnecting with the port 8 and the ports I 4 connecting with a cross-passage `I5 in the handle member 2 for the air regulator' to be next described. The throttle valve I2 has astem element I-B engaged by a lever I'I 'fulcrumed on the handle member and operable by a depressible trigger I8 to lunseat the throttle valve l 2 .from the exterior of the tool.

To mount the air` regulator, the handle member 2 is provided with a bore I9 olf-set from the outer section 5 of the main supply passage and arranged at a slight inclination thereto as shown.

The bore I9 extendsinvvardly frcm the outer end of the .handle memberto and connects with the cross-passage I5 as shown.` Located with a tight fit vin the boreIS in advance ofthe cross-passage I5 is a bushing 20, the bore 2l of which connects "with the cross-passage I5 and has an internal shoulder 22 providing a stop for the plunger ory Aair iiow controlling member of the regulator to be presently described.

The bushing 20 has ports 23, 23 on the advance i side of the stop 22, `and these ports connect with a cross-passage 24 within the handle member between the bore I9 and the main supply passage section 5. In this respect, the passage 24 connects the bore I9 with the portion of the supply section 5 between the throttle valve assembly and the inlet nipple 6 as shown in Fig. l. By this arrangement, the air iiow to the barrel I through the throttle valve may be controlled by the air regulator to provide for either a hard and fast or a light and slow hitting stroke for the hammering piston within the barrel. In this manner, the hitting power of the tool may be adjusted to accord to the rivet sizes to be upset and more perfect heading results. For a hard and fast hitting action, the bushing ports 23 are opened to the extent desired, while for a slower and lighter hitting action the ports are closed to the extent desired. The tool may be set for the job to be performed and in instruction in riveting schools the stroke may be adjusted to the very minimum.

The air regulator of my invention comprises the complete fixture shown in Fig. 2. Here, and also in the other views, the regulator comprises a body or plug portion 25 having a screw threaded section 25 at its outer end to secure the regulator within the bore I9 by engagement with the internal threads 2l therein as detailed in Fig. 1. To the rear of the threaded section 23, the plug element 25 has a tapered section 28 which ts within the tapered section 3l! at the outer end of the bore I9 and tightly closed therein against air leakage when the plug element is drawn tightly into place by the engaged threads 26, 2l. The plug element has a fiat sided wrench engageable flange 3| at its outer end for turning and tightening the regulator in the bore I9.

The plug member 25 has a central bore 32 extending through its tapered portion 28 and this bore opens through the outer end of the plug member at the flange 3| and connects at its inner end with a cylindric chamber 33 which the threaded section 26 provides. Between the bore and the chamber 33, the plug member 25 has a tapered Valve seat 34 for a tapered valve member 35 fixed on a shaft element 39. The latter is journaled in the bore 32 and turns the valve member 35 when adjusting the regulator. The shaft element 36 continues beyond the valve member 35 into a threaded section 31 to mount the air flow controlling member or plunger 38.

The plunger 38 is fitted within the cylinder 33 and has side wings or keys 39, 39 which engage in key slots di?, 40 in the threaded section 26 of the plug member to translate the turning movement of the shaft element 3E into an endwise movement for the plunger t0 open and close the ports 23 in the bushing 29. The bore 4I of the plunger 38 is internally threaded to engage the threaded section 21 of the shaft element 36 to provide for the action mentioned. A right-hand turning of the shaft element 35 adjusts the plunger 38 to close the ports 23, whereas a lefthand turning of the shaft element adjusts the plunger to open said ports. plunger 38 comes to rest on the shoulder 22 at the extreme of its outward adjustment.

To turn the shaft element, I provide the regulator with a turnable head member 42. This head member may be milled on its outer side to facilitate grasping it and is fixed to the shaft element by a cross-pin 43 as shown in Fig. 1. The opening in the head member for the pin extends therethrough so that the pin may be reached for disassembly.

interposed between the head member 42 and The outer end of the the plug member 25 are a number of ball checks tid, t4 pressed into countersinks 45, i5 arranged in a circle in the head element at its inner end about the axis of the shaft member 36. These ball checks serve to hold the head member 42 against accidental rotation and thus maintain the plunger atits adjusted positions. 'I'he spring members 45, 45 which hold the ball checks in place are mounted in recesses lll', 4l in the plug member and also hold the valve member 35 normally tightly closed against its seat 34 to prevent air leakage through the regulator along the shaft element in any adjusted position of the plunger 33. Hence, hissing of the regulator is prevented when under air pressure. The valve member 35 and its seat have a ground fit t0 prevent leakage when closed. Being circular and fixed to the shaft element 33, the valve member 35 is turned with the shaft in adjusting the plunger 38 and the lapping action which occurs maintains a leak proof joint.

The structure shown and described operates as follows: l

For a full volume operation of the tool, the air regulator is adjusted with the plunger 38 completely opening the ports 23. For operating the tool at a lesser airvolume, the head member 42 is turned against the resistance of the ball checks to extend the plunger further into closing relation with the ports 23. It will be noted that the springs iii also serve to hold the Valve member tightly closed against its seat and hence with the construction disclosed noopportunity is afforded for air leakage at the regulator. This provides a quiet acting fixture and the objectionable hissing of the previous regulators is avoided.

The details of construction and arrangement of parts shown and described may be variously changed and modified without departing from the spirit and scope of my invention, except as pointed out in the annexed claims.

I claim as my invention:

1. An air regulator for pneumatic tools comprising, a body member for mounting the regulator in its place of use, a shaft element journaled in the body member and extending'therethrough, an air flow controlling member connected to one end of the shaft element for adjustment thereby, a turnable head member connected to the opposite end of the shaft element for turning the same, a valve member carried by the shaft element between the air nowfcontrolling and body members, a seat on the body member about the shaft element for the valve, check elements on opposite sides of the shaft element and co-acting with the' body and head members for holding the head member against accidental turning, and spring means, one for each check element, for holding the check elements in operative relation to the head member and acting on the head member on opposite sides of the shaft element for normally seating the valve member to prevent air leakage through the body member along the shaft element.

2. An air regulator for pneumatic tools comprising, a body member for mounting the regulator in its place of use, a shaft element journaled in the body member and extending therethrough, an air liow contro-lling member connected to one end of the shaft element for adjustment thereby, a turnable head member connected to the opposite end of the shaft element for turning the same, a valve vmember carried by the shaft element between the air flow controlling and body members, a seat on the body member about the shaft element for the valve, ball checks mounted in recesses in the body member on oppositesides of theV shaft element and engageable with countersinks in the head memberv for holding the latter against accidental turning, and spring elements in said recesses, one for each said ball check, for holding the ball checks in the countersinks and acting on the head member on opposite sides of said shaft element for normally seating the valve member to prevent air leakage through the body along the shaft element.

v3. An air regulator for pneumatic tools comprising, a plug-like body member adaptedA to be inserted into an air supply passage of the tool and having connected cylindrical and tapered sections, said cylindrical section having ,screw threads for engaging screw threads in thegpassage for mounting the body member therein 'and drawing the tapered section of the body member into closing relation with the passage on screwing the body member into the same, a shaft element f journalled in the tapered section of thev body member and extending therethrough and having an end portion in said cylindrical section, a plunger constituting the air ow controlling member of the regulator slidably mounted in said cylindrical section and having screw threaded connection with the shaft element for adjustment thereby, key members on the plunger engaging in slots in the cylindrical section of the body member for holding the plunger from rotation, a head member fixed to the outer end of the shaft element for turning the same, a valve member carried by the shaft element between .the plunger and the tapered section of the body member, a seat on the body member for the valve aboutthe shaft element, and'spring y'means acting on the head member for normally seating the valve member to prevent air lelakagefrom the body member along the shaft element and for holding FRITHIOF P. FORSS. 

